(a) Field of the Invention
This invention relates to 5-hydroxymethyl-1,6-naphthyridin-2(1H)-ones, alkanoate esters thereof, 5-methyl(or ethyl)-1,6-naphthyridin-2(1H)-one 6-oxides, and the cardiotonic use thereof.
(b) Information Disclosure Statement
Chemical Abstracts 72, 12,615d (1970) is reproduced as follows: "Chemotherapeutics. IV. 1,6-Naphthyridine N-oxides. Takahashi Torizo; Hamada Yoshiki; Takeuchi Isao; Uchiyama Hideko (Fac. Pharm., Meijo Univ., Nagoya, Japan). Yakugaku Zasshi 1969, 89(9), 1260-5 (Japan). Various reaction conditions were examd. for the formulation of I, II, III, and IV by the application of hydrogen peroxide to 1,6-naphthyridine in HOAc soln. ##STR1## Ir, uv, NMR, and mass spectra of these four compds. were measured to detect their structure, which was detd. by chem. methods such as redn. with Raney Ni. Antibacterial action of I, II, and III was examd."
2-Hydroxy-3-methyl-1,6-naphthyridine, the tautomeric form of 3-methyl-1,6-naphthyridin-2(1H)-one, was reportedly prepared by Ogata et al. [Chem. Pharm. Bull. 20, 2264 (1972)] in two steps by first photocylization of N-(4-pyridinyl)methacrylamide to produce 1,2,3,4-tetrahydro-3-methyl-2-oxo-1,6-naphthyridine and then dehydrogenating said tetrahydro compound by heating it in acetic acid.